[Nordic]

My experience with northbridges is that they indeed can get pretty hot. I've got a Zalman NB32 which is a passive heat sink which replaced the puny heatsink/fan combo that originally was on my EpoX 8K7A. The Zalman gets very hot, I can just barely touch it which means it's in the neighbourhood of 50C and the heat is transferring just fine. My bus is not overclocked and the system is totally stable, in fact I can not tell if there is any difference in overclockability of the bus. Perhaps my memory is holding me back but I don't think the high temperature is a problem for system stability as far as northbridges go.

On a side note, a friend of mine also got himself a Zalman NB32 but on his KT266A board the sink hardly gets above body temperature, even when overclocked (166 MHz). This indicates that northbridges come manufactured with different line widths, my AMD 760 is prolly 0.25um while the KT266A of my friends machine might be 0.18um. This is only speculation but I don't think it's far fetched.